Aptamer act as fluorescence switching of bovine serum albumin stabilized gold nanoclusters for ultrasensitive detection of kanamycin in milk

We developed a fluorescent switching based on bovine serum albumin stabilized gold nanoclusters (BSA-AuNCs) and kanamycin (Kana) aptamer to detect Kana. Red fluorescence of BSA-AuNCs was turn off when Kana aptamer was assembled on the surface of BSA-AuNCs. However, after adding Kana, the specific aptamer detached from the surface of the BSA-AuNCs and formed the complex of aptamer-kanamycin, then the red fluorescence of BSAAuNCs was turn on. The fluorescence intensity of BSA-AuNCs can be mediated by the amount of Kana aptamer. A good linear response for Kana was obtained in the concentration range 0.04 nM to 7.0 nM. The assay was used to detect Kana in milk matrix, and the accuracy and recovery of the method were satisfied. It is worth noting that the aptamer mediated BSA-AuNCs fluorescent switching was simple and easy to fabricate, which can provide a novel assay for the detection of small molecules.

Automated summary

A fluorescent switching based on BSA-stabilized gold nanoclusters and kanamycin aptamer was developed for the detection of Kana. The method achieved a good linear response for Kana in the concentration range of 0.04 nM to 7.0 nM. The assay showed satisfactory accuracy and recovery for detecting Kana in milk matrix, offering a novel assay for the detection of small molecules.